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Background: Social media are currently considered as a potential complementary source of knowledge for drug safety surveillance. Our primary objective was to estimate the frequency of adverse drug reactions (ADRs) experienced by Twitter users. Our secondary objective was to determine whether tweets constitute a valuable and informative source of data for pharmacovigilance purposes, despite limitations on character number per tweet.

Research design and methods: We selected a list of 33 drugs subject to careful monitoring due to safety concern in France and Europe, and extracted tweets using the streaming API from 30 September 2014 to 5 April 2015. Two pharmacovigilance centers classified these tweets manually as potential ADR case reports.

Results: Among 10,534 tweets, 848 (8.05%) implied or mentioned an ADR without meeting the four FDA criteria required for reporting an ADR, and 289 (2.74%) tweets were classified as ‘case reports.’ Among them 20 (7.27%) tweets mentioned an unexpected ADR and 33 (11.42%) tweets mentioned a serious ADR.

Conclusions: With the use of dedicated tools, Twitter could become a complementary source of information for pharmacovigilance, despite a major limitation regarding causality assessment of ADRs in individual tweets, which may improve with the new limitation to 280 characters per tweet.  相似文献   

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Purpose

To analyze trends in second primary cancer (SPC) incidence by using a case-mix approach to standardize on first cancer site distribution.

Methods

Cases registered by 13 French cancer registries between 1989 and 2010 and followed-up until June 2013 were included. The person-year approach was used to compute standardized incidence ratios (SIRs) of metachronous SPC. Usual SIRs and cancer site–specific weighted SIRs called “case-mix SIRs” (cmSIRs) were estimated by sex and calendar period of first cancer diagnosis. Calendar trends in SIRs and cmSIRs were compared.

Results

More than 2.9 million person-years at risk were included. Among males, SIRs dropped from 1.49 to 1.23 between 1989–1994 and 2005–2010, while cmSIRs decreased from 1.40 to 1.27. This difference seems mainly related to a stronger representation of prostate cancers (at lower risk of SPC) and a weaker contribution of bladder and head and neck cancers (at higher risk of SPC) in recent periods of diagnosis. Among females, both SIRs and cmSIRs have remained stable at around 1.22 and 1.21, respectively.

Conclusions

The cmSIR is an indicator that is not influenced by changes in first cancer site distribution. Its use should be encouraged to assess second cancer incidence control.  相似文献   
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Objective: To conduct a literature review to determine the types of information that existing dermal pesticide monitoring data could provide for future pesticide exposure assessment in occupational epidemiology.

Methods: A systematic literature search was performed on eight online databases. Two screening phases with predetermined criteria identified the qualifying literature. Standard information and dermal pesticide monitoring data were recorded and summarized from each qualifying study to assess its usefulness for future pesticide exposure assessment.

Results: A total of 31 farm studies qualified for review; task information was used to standardize all farm job(s) evaluated into 5 job groups: operators, applicators, mixer-loaders, field workers, and flaggers. When attempting to compare dermal exposure levels between studies, two types of variation were identified: (1) variation in study focus and reporting and 2) variation in exposure levels. The former variation type prevented exposure level comparisons between studies. Within studies, exposure levels were compared across body parts to identify that which had the highest measured exposure and to determine if results were similar in other studies that evaluated the same farm job. Using studies that measured exposure for multiple farm jobs, within study comparisons of total body exposure were performed to evaluate work factors.

Conclusion: Future dermal pesticide exposure monitoring studies should standardize reporting procedures, as suggested in this review, to allow for more extensive dermal data comparisons. Body parts with highest measured levels of dermal exposure were identified by farm job, along with work factors to be further investigated as potential dermal pesticide exposure determinants for farm workers.  相似文献   

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